Intimate Knowledge
by tiltedsyllogism
Summary: Everyone kills for a different reason. Sherlock's got to understand somehow. **** A remix of Keerawa's story Murder Will Out, which you can find on archiveofourown dot org, here: /works/404483


John's mobile rang just as he was leaving Tesco. It was lunchtime, and the sidewalk was packed with people taking advantage of a beautiful day, so he ducked into the doorway of a nearby office building. Leaning up against a pillar, he set down the shopping and clicked accept.

"Commander," he said. "How's it look from the top of the world?"

"Yeah, it's all peachy." Lestrade's voice blurred at the edges into the thick wall of background noise. From the sound of things, his new office had ongoing road work taking place in the central hallway. One of the grocery bags had tipped, John noticed, so he stooped down quickly to tuck the bread and the sausages back in, then stood and plugged his finger into his other ear.

"Is this Samuels calling in the big guns?" he asked.

Lestrade sighed in a burst of static. "It's a complete cock-up, John, this Waterston case. The team's a mess, nobody can tell their arses from their elbows. The papers are all over it…."

"Yeah, saw that," John muttered.

"Well, you didn't see the bit about the profiler, they've kept that back so far. But it's only a matter of time before someone on the investigative team spills the beans. Bunch of fucking amateurs. The Chief Superintendent's starting to get heat about that, by the way, for putting a team of greenhorns on it."

"That's got to be uncomfortable for you," John remarked.

"You think? Just a second, hang on." The line went blurry as Lestrade covered the phone, the hazy traces of a conversation filtering through. A moment later, he was back. "Anyhow. Sorry about that. But yeah. Can you try to get Sherlock on board? We're in a pretty bad way over here."

"Well, you know he doesn't care about that." John squinted out into the sunlight. "But I'll try again. He's just home on the sofa, otherwise. If you've got any ideas, I'd love to hear them." Lestrade had intimated, back during the Study in Pink case, that John already knew Sherlock better than he did himself. By now, nearly three years into living at Baker Street, that was certainly the case. But still, history counted for something.

But Lestrade only sighed again. "Haven't a clue. To be honest, I don't know why he didn't snap it up in the first place – it seems like just the sort of thing he'd like. Bloody confusing. And just bloody."

John nodded absently into the phone for a moment before he caught himself. "Yeah, I'd have thought so too. To be honest, Greg, he'd never admit it, but I think he misses you."

Lestrade let out a nasal squawk that probably indicated skepticism. "Nobody around to take his shit, you mean."

"Well, there's still me. But yeah, I think the idea of an all-new team's got him spooked." John chuckled. "I think he'd even be happy to see Donovan, at this point."

"Change comes hard to us all, innit," said Lestrade.

"It's a hell of a promotion," John said. "You like it up there?"

Lestrade sighed. "Honestly, I'm still not sure. Never thought I'd say this, but I miss dealing with people. And then there's the paperwork, John, you wouldn't believe it."

"Well, don't let the power get to your head." John glanced down at the shopping and frowned. It was quite a warm day. "Look Greg, I'll talk to you later, I've got to…"

"Yeah, me too. Bye, John. Be in touch if you think there's anything I can do to mollify His Nibs."

"You'll be my first call," John said, and rang off. He stared down at the package of sausages and tried not to think about what the murderer had done to Emily Waterston's fingers.

John shook his head. It wasn't even their case. He gathered up the shopping and set out for home.

Their fourth case together was the first that was really gory; a well-dressed man, early middle age, found in an alley off of High Street with his eyes cut out. When Sherlock and John arrived, the police were mostly focused on high-quality leather satchel that lay beside the corpse, cut into neat strips and soaking up water from the filthy ice-rimmed puddles. But that all changed when one of the forensic techs – a steady, brisk young woman who was more inclined than most to cooperate with them – pried the man's mouth open at Sherlock's directive and pulled his severed eyeballs out from between his teeth. The tech went pale, and seemed to be struggling not to toss them away. Even Lestrade looked stricken.

"Wow, that's. That's. Christ," John said.

"Intriguing," Sherlock said.

It was an image to stick with one, and it followed John into the cab; they were halfway to Baker Street when John caught sight of his own reflection in the window and saw how he was huddled in on himself. Well, it was cold. He straightened in his seat and folded his hands in his lap. Next to him, Sherlock fiddled away on his mobile, apparently oblivious to the presence of lesser beings not equipped with bluetooth. But then:

"Spooked?" Sherlock's voice was flat; and his face was so still, on the other side of that single clipped syllable, that John wouldn't have sworn he had spoken at all.

"A bit," he went ahead and replied anyway. Sherlock seemed perfectly happy to jump in and answer questions John hadn't got round to asking, so why not. "It's just."

Sherlock was still staring at his phone, but he seemed like he might be listening, so John plowed ahead. "Killing is one thing. Sometimes it's necessary." He paused. "Or you get very angry, I suppose. Not that it's… Well. But it does happen, and it's… understandable. But it." He pursed his lips, casting about for the right words. Conversations with Sherlock were teaching him the virtue of precision. "It's hard to imagine, I suppose, what would make someone. Why they would do –" he waved his hand " – _that_. To another person. How it could seem… dunno. Good. Satisfying. Like it would do something."

Sherlock offered only a neutral hum in return, which John couldn't help but feel was a bit unfair, after all that. But then his eyes flicked to John, briefly. "What do you think," he asked, the question flattened into that same tone.

John raised his eyebrows and pursed his lips. "What do _I_ think." He folded his arms. "Well. I suppose if I…. wanted to punish somebody for, hmm, seeing something they shouldn't. Or if I, dunno, felt spied upon." He grinned. "If I were ever going to kill your brother, maybe.

"So how's that, then," he continued, when Sherlock said nothing. "How close did I get?"

But Sherlock only smiled at that. Smug bastard.

Sherlock hadn't meant to smile. He controlled his face and stared at his mobile screen, nearly thrumming with excitement and very much hoping that John would continue to be oblivious to that fact. John was more or less predictable in his actions, but his reasoning was often perplexing, and so Sherlock was delighted to have this unexpected window into his head.

It wasn't about psychology, or not in the way John thought – he had obviously been fed Jung (or some dilute psychobabble digest of Jung, in all probability) at an impressionable age. Popular media only perpetuated the myth that people killed in response to some sort of desperate or uncontrollable drive. Of course such killings did occur occasionally; but most murderers had reasons, things that they wanted or needed to accomplish. Situations that did not seem resolvable in other ways. The particularities of a given murder were revealing, to be sure, but –

"Sherlock?" John seemed annoyed. Oh.

"Yes, a good effort," he said magnanimously. "It's nothing to do with the scene we examined, but I imagine there's a television scriptwriter somewhere pressed for time who would find your theory adequate."

Sherlock wasn't looking, of course, but he couldn't help noticing out of the corner of his eye how John's face passed all in a moment from crestfallen, to perplexed, to concerned, finally stopping at irritated. Sherlock's tone had been perhaps a bit brisk.

"Yeah, all right," John said at last, and Sherlock returned his web research, unaccountably relieved.

But then a moment later that level surface broke. "Why even bother, Sherlock? It's fun for you, is it, watching me flail about, getting everything wrong?"

It was an unpleasant feeling, having upset John; Sherlock decided to placate him with explanation. "Every murderer's motivation is slightly different. There's the person they kill, of course; but more importantly, there's the reasoning, and the method." Sherlock had given this speech many times, to various audiences, in his head; to himself most frequently. It sounded a bit strange, spoken out loud. "Furthermore, not every problem needs to be solved by killing; a given individual turns to murder only when faced with the particular kind of problem that seems, to him or her, best addressed in that way. Understand the line of reasoning that lies behind the killing, and you'll understand your murderer." _And you_ , he didn't say.

John was uniquely worthwhile as an audience, for reasons Sherlock did not yet himself entirely understand; but he was also peculiarly interesting as an object of study, and John's theorizing, though it had no practical application as pertained to the case, constituted a promising new vein of information about John himself. True, the direct utility of such information was nebulous at best; even an ordinary subject's process of retrospective deduction about somebody else's activities offered, at best, a limited sort of insight into that subject's own range of possible future actions.

But it had been nearly a month since that night at Roland-Kerr, and John hadn't yet killed anyone else. Sherlock had to admit that it was possible that it wouldn't happen again. It offered a frustratingly imprecise index, observing John as he engaged in second-hand speculation about some other killer's impetus and executive logic, but Sherlock had to populate his data set somehow.

John wrinkled his brow, obviously considering. "So it's like poker, then? He'll have a tell?"

It was actually an interesting analogy, and one which wouldn't have occurred to Sherlock, who didn't play cards (although of course he knew the rules). Perhaps it was John's tell that he was after. The affair with the cabbie had given Sherlock a lot to think about, but he had eventually concluded that the circumstances, while themselves highly revealing, were only so much distracting clutter, in the end. Kill a known murderer in the act: obvious. Use the one means available for doing so from a distance, in the face of evident time pressure: also straightforward. But these exigent conditions, while valuable as a general index to John's moral outlook, also meant that Sherlock still knew practically nothing about how John would choose to take a life, under less artificially controlled circumstances: at what point in a developing situation he would deem it necessary, what method he would employ to take the life he had decided to end. John had a strong commitment to justice, if not to strict legality, so perhaps he would explain things, Sherlock thought, up to the very finish. Or perhaps he wouldn't, perhaps he would be ruthlessly silent; but even that would speak volumes, coming from John, who managed to say so much with his face and his movements.

"Everyone does, John."

"Huh?" John replied. "Oh sorry, didn't realize we were still talking."

"We're always talking," Sherlock replied. "At least, you are."

John was about halfway back to Baker Street with the shopping when a sleek black car rolled up to the kerb beside him. Perversely, John was almost relieved: whatever fuckery Mycroft planned to throw at him would surely follow him home in the look on his face or the squeak of his shoes or some other tiny sign Sherlock would instantly recognize. A Mycroft kidnapping ought to be good for at least a few minutes of rage, and that was before one reckoned with whatever it was Mycroft actually wanted to talk about. Sherlock's tantrums weren't much fun, but they were better than the long silences. John hadn't said anything to Greg about it, but he was beginning to worry.

John climbed into the car and set the bags down on the floorboard. He was alone in the rear of the car this time, which was odd, but not unpleasant. Nobody to make him uncomfortable in that plush, quiet car. Except for himself, of course, which did nicely.

The car took him only about fifteen minutes away, to a nondescript office building off the A41, pulling up to a service entrance round the back. With nobody to ask but the driver – and John didn't much fancy knocking on the tinted glass that separated the front compartment from the back, or going round to knock on the window – he left the groceries in the car. The building door was propped open with what looked like a piece of discarded plastic shelving, and it led to a bare hallway with several doors, one of which stood open. John knew the drill.

The room appeared to be some sort of basement office, and even appeared to be in regular use. As Mycroft rose from the chair behind the desk, John noticed framed photographs propped up next to the computer monitor. There was also a small stuffed creature (woodchuck? badger?) stuck to the side of the CPU with plastic suction cups, and a calendar on the wall with dog cartoons, so John didn't fancy it was worth his time to get a closer look at the photos.

"Doctor Watson," said Mycroft, evidently out of patience for John's survey.

John folded his arms loosely. "Not quite your usual digs, is it?" John asked.

"Exigent circumstances," Mycroft replied. "You won't sit down, I suppose."

There were chairs set up in front of the desk, but John remained where he was, only a few steps past the doorway. "Is this going to take long? Only I've left the milk in the car."

But Mycroft remained silent, eyes flitting between John and the doorway, the calendar, the organization chart on the far wall. Having seen Mycroft inhabit a dozen different versions of haughty-and-put-out, John found himself wondering whether there wasn't some real anxiety in the mix this time around.

"Did he ever tell you about the cat, John?" Mycroft asked at last.

It took a moment for John's throat to unstick itself. "Yeah," he forced out. "Knew about that." It wasn't something he liked thinking about – that whole conversation had rather shaken him, really – but he remembered well enough. John had always kept a cool head during these little meetings with Sherlock's brother (the anger came much later, in brief loud bursts) but he was suddenly angry. What business was it of Mycroft's to go poking into this stuff?

"He doesn't mind, you know," John said tightly. "Telling me things. I think it helps that I don't threaten him regularly." He folded his mouth into a fierce impression of a smile.

But Mycroft only nodded. "Her name was Elizabeth," he said after a moment.

"Elizabeth." John racked his brain a moment, then shook his head. "Yeah, sorry, I don't know who that is."

"The cat." A pause. "There was a great deal of therapy, John, a large number of professionals involved. The primary specialist with whom I consulted at the time was adamant on the point. There needed to be a story that everybody could live with."

John shifted impatiently. He had a pretty good handle on how therapy worked – you had to face the things that could happen, put them into the story you told about yourself – and Mycroft, of all people, should know that about him.

Mycroft gave a small sigh that seemed to be his adaptation of Sherlock's eye roll. Or the other way around, John supposed, since Mycroft had come first. "And of course it required a large sum to compensate the family."

John frowned, confused. Whatever Mycroft considered a large sum was probably more money than John knew how to think about. Who paid out that kind of money over a dead cat? He had already opened his mouth to form the words when the truth begin to seep in cold at the back of his throat.

John no longer found Mycroft generally alarming. At least not very much. But now, as he stared at the elegant, implacable figure who continued to lean on his umbrella as though this were any other conversation – as though this were their first meeting, when things were easy and Mycroft was clearly the sinister one – John felt a cold twist in his gut that was like embarking on a long stretch of road seeded with IEDs. No, a bit different; it felt like the second after the vehicle behind yours had exploded, before you had even managed to turn around, before you knew who was alive and who was in pieces all over the road.

Mycroft watched him back, taking in his slow-dawning horror. "It was a story we could all live with," he repeated softly.

John suddenly wished there were a chair nearby. Just to lean on for a bit. "You… How could you…" He felt his hand threatening to shake and clenched it tight at his side. He blinked hard, to steady himself. "And he still doesn't know?"

"It seemed best at the time, John," Mycroft replied, with a touch of acid reproof. But then he dropped his gaze, pressing his lips together briefly, and when he looked up again, he seemed still unable to meet John's eyes. "It had only been the once."

"Yeah, well." John rubbed the back of his neck, ground the heel of his hand along his thigh; any kind of gesture to make space around him, keep back the new history that was pressing in, threatening to rewrite the past three years of his life in a more ominous language. "You couldn't know that it would stay that way, did you."

"No, John," Mycroft returned, his voice all delicate shades. "We didn't."

John tipped his head back. "So what, I'm supposed to – just…." He pushed his hand back through his hair. It was a gesture he'd picked up from Sherlock. "You've got shit timing, Mycroft. There may not be a case on, but it's not a good time for him and me to talk about… this. Thing." He pursed his lips. "Which I assume is what you want from me, yeah."

Mycroft's smile was like dead grass. "As busy as your schedule is, John, perhaps take a moment to consider that I am now, as ever, quite thoroughly taken up in other matters."

"Right." John pursed his lips and swallowed hard. "Elections to rig, enemies to destroy, the whole bit. And me. I'm to do what, exactly?"

"Think about it, John," Mycroft replied, and John looked up sharply at the difference in his voice, all the archness drained away from it. Without the starchy hauteur, he seemed tired, and maybe a bit sad. "Just think about it."

John turned around without another word and walked out. The sunlight came as a dull shock as he stepped out into the alleyway. He felt numb as he got back into the car, and stared at his shopping like he had never seen such a thing before. He folded his hands in his lap, and watched as his knuckles slowly went white. Something chilling, vast and cold like an ocean without horizons, was pressing in on him. He stared out the window as the car pulled away and tried deliberately not to think. Mycroft had a talent for making things murky and elusive, a sort of a mirror to his brother's talent for making confusing things clear. It was no contest as to whose methods John preferred. But Mycroft had, in his own elliptical way, been trying to communicate something important, and now John fought off the encroaching clarity with every ounce of energy he had left.

It came out unexpectedly, on a day when they hadn't yet spoken at all. John had come back from Sarah's in the early afternoon, cheerful in spite of the rain, and then pottered around the living room while Sherlock dissected a decomposing tongue in the kitchen. The living room was empty when Sherlock emerged from the kitchen a few hours later, filled with the cool grey light of late afternoon. John's coat was over the back of his chair, but his phone wasn't in the pocket, so Sherlock stretched out on the couch to listen to the creak of the floorboards and the occasional muffled exclamation as John paced in his bedroom above.

At last the door creaked open. Sherlock steepled his hands beneath his chin. His eyes remained closed as John tromped down the stairs. John paused at the foot of the stairs, eyeing the phone in his hand.

"Your mother." Sherlock diagnosed, his eyes still closed.

"Yeah," John said. "Usual tosh about bridge club, whose annoying little dog is bothering someone else's little dog. Drives me mad to hear it all." He tossed his phone down on the coffee table and let out a deep breath. "But, well."

Sherlock opened his eyes and watched John as he settled himself in his chair. "Well what."

"You know what it's like," John said.

"Not really," Sherlock said.

John wasn't sure how to take that. In some ways, Sherlock didn't seem to have any boundaries at all, inviting himself on John's dates and experimenting on his food, but then also occasionally giving him possessions when the thought struck that John could use them better than Sherlock could. But on the other hand, the man never seemed to meet a question he didn't like, in the sense that he didn't bother meeting most of John's questions at all.

"Mum not have a bridge club?" he ventured.

"Dead," said Sherlock briefly.

John felt this knowledge settle into place – _obvious_ , Sherlock might say – even in the aftershock of contact with significant information. "Oh, um. Sorry. About. That's. Must be difficult. I mean…"

Sherlock held up a hand. "Stop," he said, and John subsided. "It's fine. It was many years ago. I barely remember her."

John sat quiet a moment, feeling vaguely guilty for having trod somewhere intimate, a place that Sherlock couldn't control. He had wondered about Sherlock's parents, of course, because who wouldn't. But he hadn't expected this; he'd looked at the posh clothes and assumed that Sherlock had always had everything anyone might have wanted.

"Were you very young?" he offered at last, keeping his voice neutral.

"Hmm?" Sherlock's attention seemed to have wandered in the interim. "Oh. I was eight." He waved a hand. "There was a great deal of therapy. I don't remember very much of it. The electroshock treatment was uncomfortable."

"Electroshock." John blinked a few times, hard. That one was a surprise all the way down. He wondered if that was how the other half coped with tragedy, when they had to. Privately he thought it seemed a bit thick, this whole routine of dead-mum-what-a-lark; he wondered if Sherlock had ever really had a chance to grieve at all, or had simply buried it. Or maybe he was fine, and just very private about it all. John couldn't pretend to understand him very well.

John's face was being fascinating again as he plodded through the fairly simple information that Sherlock had given him; Sherlock sat up to watch properly. He still couldn't understand why it took everyone so long to make sense of things that were fairly simple, but watching John had given him the beginnings of insight into more ordinary minds. To look at John, it seemed as if he (and perhaps he was representative in this respect, for John was essentially ordinary, that much had been clear right away) had to stop and examine every thought and feeling one by one. The unfolding symphony of expressions – most of which Sherlock had not yet succeeded in matching definitively to a particular underlying emotional response – was captivating. He waited, almost patiently, for John to work his way up to the question Sherlock knew would come next.

"How was –" John flicked his hand in Sherlock's direction, as if the gesture compensated for his lack of verbal precision or facility. "What made them think it would help you grieve?"

Ah. Not precisely the question he had anticipated, after all. There was always something, Sherlock supposed. At least at first. With John, perhaps, there would always be something.

"That was… different. Behavioral adjustment."

John blinked. "Were you. Um. Acting out?"

Sherlock shifted to perch on the very edge of the sofa. It was that, or lie back down again. "I killed a cat," he said offhandedly. "It belonged to one of our maids."

"Oh." John's brow furrowed. "Did you… on purpose?"

Sherlock couldn't help an impatient scoff. "Yes, on purpose." He didn't remember much, other than the warm red feeling of living organs under his hands. It had been – as his therapist had said, as Mycroft had said – a bad time. He'd been a stranger to himself, in the weeks after his mother's death, and Mycroft had been useless, too self-involved to pay attention until there was something to be angry about.

Sherlock realized that John had been quiet a long time. He glanced up to find his flatmate staring down at his own sock feet, his fingers tracing idly over the arms of his chair.

"It was a bad time," he offered.

John looked up at him at last. "Yeah," he said uncertainly. "Everyone has them." His eyes softened. "I'm after tea. Do you want some?"

Sherlock felt, for some reason, absurdly grateful. "Yes."

"All right," John said. He levered himself up from his chair and walked into the kitchen, but not before leaning across the coffee table and touching Sherlock briefly on the knee. Sherlock felt a flush of happiness, as though the tea were already inside him, a touch of warmth on a grim and rainy day.

Sherlock lay on the sofa, hating everything. The sunshine only made everything worse. Today was, in its fundaments, gloomy and miserable. London ought to give a more honest report of itself.

The sound of a key, scraping as it turned in the front lock, wafted in through the window, made crisp and clear by a lull in the street noise. Mrs. Hudson was puttering in her kitchen downstairs, so this was John, back from the shops. A heavy tread on the stair; frustration. Long lines at the register, then. But no: several seconds before the next step signaled hesitation, distress. Yet the heaviness of each step, as John continued his slow climb, confirmed Sherlock's initial assessment as well. And a slight mismatch in the pace: the bags were weighing heavily. Distraction and distress.

He had worked it out, then. Sherlock had supposed – hoped, even – that John would eventually twig to the reason why Sherlock had so adamantly refused the case, but he was surprised and pleased that John had managed it so quickly. He must be absorbing some of Sherlock's methods, after all.

John unlocked the door, slowly, and came to a stop just over the threshold. Shoulders hunched, no shopping bags with him. Interesting. Sherlock quickly recalculated. He had significantly underestimated John's anguish and consternation. And the anger as well.

"Sherlock. Can we talk?"

John was clearly upset; he would likely yell. He might even want Sherlock to confess, at first, before the reasoning had been made clear to him. It was a bad thing to have done, Sherlock knew. But the circumstances had been legitimately extreme. The police were irritating at best, but they were an essential part of the Work. Sherlock had needed a diagnostic, he had needed to understand what kind of a team he would be working with. And Emily Waterston was a junkie. Junkies were more or less expendable; he knew that from the inside.

And it had only been the once.

"Of course," Sherlock said. He dropped his eyes; diffident, even penitent. Surely the conversation would be easier if John saw at the outset that Sherlock was aware of his misstep.

Sherlock rose fluidly to his feet, eyes still cast down. He bit his lip, a gesture that telegraphed both uncertainty and discomfiture under scrutiny, and slumped his shoulders slightly. He risked a glance back up, to monitor the effects, and found John watching him intently. His jaw was set and hard, and in his eyes was something like despair.

John made no move to his chair. "Upstairs," he said. "Let's talk upstairs." John's voice was flat and empty, and his face was hard in a way Sherlock had imagined many times, but had never seen.

Sherlock nodded. He felt a strange clenching in his throat, which he ignored in favor of the bright trill of elation that was growing inside of him. He stood slowly, deliberately, savoring it. He was finally going to understand about John.


End file.
